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You can add a mic, speaker and amp but it would be a seperate unit totally and the audio wouldn't be recorded on the DVR since the DVR hasn't gotten any audio inputs.

Intruder / CCTV / Access Control Technical Support Personal

Subscriber to the "K.I.S.S" principle, that's Keep It Simple Stupid, are you?

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Well as I said you can have audio seperatly just get a suitable mic hook it up to an amp and either a speaker or a set of headphones - you could also plug it into a laptop or a PC which could be viewing the DVR footage that way you have audio in the same place and it might be possible to record the audio on the laptop/PC but how long you could record the audio for depends on the quality you want, since it would be mono it makes the calculation slightly easier but there wouldn't be any form of compression on it which would save you hard drive space.

Here's an example - standard sample rate of 44Khz and using 16-bit (will cover all audiable frequencies and give good quality) would take 88K/s to store roughly, you could lower the sample rate - type ones are 22Khz / 16Khz but they would only cover 20Hz-11Khz and 20Hz-8Khz respectivly as the sample rate has to be twice the max frequency your picking up, you could drop the quality to 8-bit which would half the storage but you wouldn't lose any of the higher frequency stuff.

All you'd need to do is find some way of putting a Time / Date Stamp on the recording and save say "hour" segements.

I'm not saying it's not possible there is no doubt software out there to do this, but you may be better seeing if the DVR you have can't be upgraded to have audio included.

However if all you want to do is Hear the audio not play it back then anything that accepts a mic input and has a headphone / speaker output would do.

Intruder / CCTV / Access Control Technical Support Personal

Subscriber to the "K.I.S.S" principle, that's Keep It Simple Stupid, are you?

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Well as I said you can have audio seperatly just get a suitable mic hook it up to an amp and either a speaker or a set of headphones - you could also plug it into a laptop or a PC which could be viewing the DVR footage that way you have audio in the same place and it might be possible to record the audio on the laptop/PC but how long you could record the audio for depends on the quality you want, since it would be mono it makes the calculation slightly easier but there wouldn't be any form of compression on it which would save you hard drive space.

Here's an example - standard sample rate of 44Khz and using 16-bit (will cover all audiable frequencies and give good quality) would take 88K/s to store roughly, you could lower the sample rate - type ones are 22Khz / 16Khz but they would only cover 20Hz-11Khz and 20Hz-8Khz respectivly as the sample rate has to be twice the max frequency your picking up, you could drop the quality to 8-bit which would half the storage but you wouldn't lose any of the higher frequency stuff.

All you'd need to do is find some way of putting a Time / Date Stamp on the recording and save say "hour" segements.

I'm not saying it's not possible there is no doubt software out there to do this, but you may be better seeing if the DVR you have can't be upgraded to have audio included.

However if all you want to do is Hear the audio not play it back then anything that accepts a mic input and has a headphone / speaker output would do.

You can get a Mic pre amp with AVC froms omewhere like Maplins for live audio........but are there not Data Protection issues with recording audio ?

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You can get software for pc's that records audio straight to mp3, so its highly compressed.

I have easy hi-q recorder on my laptop, it ok, sometimes has problems though, but that could just be my old laptop.

When its working its pretty configurable, you can set the compression ratio, the recording lengths, have it record all the time or on audio only etc.

There will be lots of other similar packages out there that can do the same stuff, just google for them.

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CHECK THE DATA PROTECTION MANUAL IT EXPLAINS ALL THE AREAS OF RECORDINGS

cheers GUYS

Be careful with audio, it is a potential minefield I think. The difference between alarm regs and CCTV regs is that contravention of the DPA, RIPA and FOI Act can lead the end user to personal criminal prosecution.

Re DPA CoP on audio See...............

"CCTV must not be used to record conversations between members of the public as this is highly intrusive and unlikely to be justified. You should choose a system without this facility if possible.

If your system comes equipped with a sound recording facility then you should turn this off or disable it in some other way.

There are limited circumstances in which audio recording may be justified, subject to sufficient safeguards. These could include:

Audio based alert systems (such as those triggered by changes in noise patterns such as sudden shouting). Conversations must not be recorded, and operators should not listen in.

Two-way audio feeds from

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can any one tell me if i have a dvr without audio on board is there any way i can have audio via a amp or type device

cheers

You'll have to change the dvr to one with audio recording. make sure the one you use has lip sync audio recording otherwise your stuffed.

Kind regards

Stuart Onley

SAMS Consultancy

Independent Security Consultants

email:enquiries@samsconsultancy.co.uk

website:www.samsconsultancy.co.uk

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You'll have to change the dvr to one with audio recording. make sure the one you use has lip sync audio recording otherwise your stuffed.

thanks for that peice of imformation ilkie i have warned the customer that it will be a end user problem and not mine if they wish to use audio then it on there heads

but thanks again for thr usefull help

regards

andy

amb alarms

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upgrading the motherboard on the dvr, could be a very costly upgrade and I doubt it is available to do. I would seriously look at an expansion board (PCI if available) to add audio to the system. Alternatively it looks to me like a new dvr system is the only viable option...

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upgrading the motherboard on the dvr, could be a very costly upgrade and I doubt it is available to do. I would seriously look at an expansion board (PCI if available) to add audio to the system. Alternatively it looks to me like a new dvr system is the only viable option...

This depends on whether the DVR is based on a PC chassis. For an embedded DVR PCI cards are not normally available.

Kind regards

Stuart Onley

SAMS Consultancy

Independent Security Consultants

email:enquiries@samsconsultancy.co.uk

website:www.samsconsultancy.co.uk

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i decided to go with the dvr without audio explained to the customer the sensitivity of its functions and she agreed in principle that we shall not have audi however i did manage to persaude her now she has a fully funcional dvr system and is happy with that thanks for the help guys

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